Proface APL3000B - Node Box PC - Manual (Page 76)

Chapter 3 Installation and Wiring
3-21
3.3.3 Grounding
This section describes the precautions for grounding the PS-B unit.
• When supplying power to the PS-B unit, be sure to separate the
input/output and power lines, as shown. [diagram (a)]
• If exclusive grounding is not possible, use a common ground-
ing point. [diagram (b)] A grounding or equivalent should be
used for the grounding point.
Do not use common grounding, since it can lead to an accident or machine breakdown.
• Check that the grounding resistance is
100
Ω or less.
• FG and SG terminals are internally
connected in the PS-B. When
connecting an external device to the
PS-B using the SG terminal, be sure to
check that no short-circuit loop is
created when you setup the system.
• The grounding wire should have a cross
sectional area greater than 2mm
2
.
Create the grounding point as close to
the PS-B unit as possible, and make
the wire as short, as possible. When
using a long grounding wire, replace the
thin wire with a thicker wire, and place it
in a duct.
• If the equipment does not function properly
when grounded, disconnect the ground wire
from the FG terminal.
(a) Exclusive Grounding (BEST)
(b) Exclusive Grounding (OK)
(C) Common Grounding (Not OK)
PS-B
PS-B
PS-B
Other
Equipment
Other
Equipment
Other
Equipment